1MST

CRYSTAL STRUCTURE OF MS2 CAPSIDS WITH MUTATIONS IN THE SUBUNIT FG LOOP

Summary for 1MST

• Entry DOI: 10.2210/pdb1mst/pdb
• Descriptor: BACTERIOPHAGE MS2 CAPSID (2 entities in total)
• Functional Keywords: bacteriophage coat protein, icosahedral virus, virus
• Biological source: Enterobacterio phage MS2
• Cellular location: Virion (Potential): P03612
• Total number of polymer chains: 3
• Total formula weight: 41173.31

Authors

Liljas, L.,Stonehouse, N.J. (deposition date: 1995-08-30, release date: 1996-03-08, Last modification date: 2024-05-22)

Primary citation

Stonehouse, N.J.,Valegard, K.,Golmohammadi, R.,van den Worm, S.,Walton, C.,Stockley, P.G.,Liljas, L.
Crystal structures of MS2 capsids with mutations in the subunit FG loop.
J.Mol.Biol., 256:330-339, 1996

PubMed Abstract: The loop between the F and G beta strands (FG loop) of the bacteriophage MS2 coat protein subunit forms inter-subunit contacts around the 5-fold and 3-fold (quasi 6-fold) axes of the T=3 protein shell. In capsids, the loop is found in two very different conformations, one in B subunits, which form the 5-fold contact, and one in A and C subunits, which form the quasi 6-fold contact. One proline residue, Pro78, is strictly conserved in the coat protein of all related bacteriophages, and in the case of MS2 this proline residue is preceded by a cis peptide bond in the B subunit. In order to probe the role of the FG loop in capsid assembly, we have determined the crystal structures of two MS2 capsids, formed by coat proteins with mutations at two positions in the FG loop, P78N or E76D. These mutants show conformational changes in the FG loops that explain the reduced temperature stability of the capsids. The P78N mutant has a normal trans peptide bond at position 78.

PubMed: 8594200
DOI: 10.1006/jmbi.1996.0089

Experimental method

X-RAY DIFFRACTION (2.6 Å)